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Flower bud differentiation is the commencement of plant reproductive development. Flower organ specialization follows flower bud differentiation. This biological mechanism controls whether plants reproduce successfully via seed. Caucasian clover (Trifolium ambiguum) is used in mixed temperate pastures. However, its low natural seed setting rate contributes to a low seed yield. This study aimed to elucidate how the reproductive biology of Caucasian clover could affect seed production. Caucasian clover flower bud differentiation and flower organ development were systematically examined. Flower bud differentiation has six consecutive stages: pre‐differentiation, differentiation of the inflorescence, the floret, the perianth, the stamen, and finally the pistil primordium. The anther has two chambers. Pollen grains have six development phases: the tetraspore, early‐uninucleate, late‐uninucleate, vegetative cell and germ‐cell form, binucleate, and maturation phase. The microspore tetrad is tetrahedral, and the mature pollen grains are bicellular. Pollen grain viability was found 35%. The Caucasian clover monocarpelate ovary contains 1–2 ovules that are covered with a 2‐layer integument. The ovule is anatropous. The embryo sac development type is a polygonum. The floral formula is "⚥↑K(5) C1+1+2 A(9)+1G(1:1:1−2)". These genetic traits of two pollen sacs and low viability pollen grains may be responsible for the low natural seed setting. Poor seed setting may also be due to embryo sac dysplasia that leads to ovule sterility. Therefore, the breeding aim should be to improve pollen viability, to decrease embryo sac dysplasia and to reduce embryo abortion that could be targeted for genetic improvement to enhance seed yields. [ABSTRACT FROM AUTHOR]

Background: Phosphorus (P) deficiency in acidic red soil restricts crop yield. However, long‐term application of phosphate fertilizer can cause potential environmental risks due to the accumulation of P in the soil. Aims: Our aim was to determine the distribution characteristics of P fractions in acidic red soil profiles and the environmental risk of soil P losses after application of organic fertilizer and lime, and analyze the key factors driving P distribution in the soil profile of acidic red soil. Methods: Based on the long‑term applicationof fertilizers and quicklime in the acidic soil under wheat–maize rotation system, contents of soil Olsen‐P and CaCl2‐P, as well as pH, at multiple soil layers between 0 and 50 cm depths were monitored. The environmental critical P levels were determined using a two‐segment linear model. Results: During 1990–2010 and 2011–2014, application of phosphate fertilizer or quicklime on acidic red soil significantly (p < 0.05) increased the annual average aboveground biomass of wheat and maize and P recovery efficiency. Soil Olsen‐P and CaCl2‐P contents increased with the application of phosphate fertilizer, especially in combination with manure, and the increase mainly concentrated at the 0–20‐cm soil layer. The environmental critical Olsen‐P content was 99.7 mg kg−1. The Olsen‐P contents at different soil layers were mainly affected by cumulative P and organic P inputs, but were less affected by soil pH. Conclusions: The application of organic fertilizer and lime can prevent the acidification of red soil, and the application of organic fertilizer should reduce the total phosphate fertilizer input to prevent rapid accumulation of P and risk of P loss in leachate while still improving the crop utilization rate of P fertilizer. Thus, this strategy should help achieve the concomitant goals of high crop yield and environmental protection. [ABSTRACT FROM AUTHOR]

Microbial immobilization of nitrate (NO3−) is considered to be an important process in reducing NO3− accumulation and regulating nitrogen (N) retention capacity in soils. Accurately quantifying the rate of microbial NO3− immobilization is, therefore, necessary to predict its role in lowering NO3− accumulation in soils. We compared microbial NO3− immobilization rates using a 15NO3− labelling technique in three different ways: (a) 15N pool dilution, (b) organic 15N recovery and (c) microbial biomass 15N recovery, in a nitrate‐rich upland soil with and without amendment with organic materials with differing carbon‐to‐nitrogen ratios (C/N). The three methods generated similar NO3− immobilization rates, except when the soil was amended with easily decomposable organic materials (glucose and sucrose). We also developed a microbial NO3− immobilization‐specific quality index that incorporates the C/N ratio, lignin, cellulose and hemicellulose contents and pH for slowly decomposing organic materials (plant residues). This study provides direct empirical evidence that the results of different methods for calculating soil microbial NO3− immobilization rates are affected by the characteristics of organic materials added to the soil. Highlights: Three methods for estimating microbial NO3− immobilization were comparedThe methods generated similar NO3− immobilization rates when amended with plant residuesHigher NO3− immobilization when measured with 15N dilution with readily available C inputA microbial NO3− immobilization‐specific index for plant residues was developed [ABSTRACT FROM AUTHOR]

The traditional Chinese herb Lonicerae Japonicae Flos has shown significant clinical benefits in the treatment of heart failure, but the mechanism remains unclear. As the main active ingredient found in the plasma after oral administration of Lonicerae Japonicae Flos, chlorogenic acid (CGA) has been reported to possess anti‐inflammatory, anti‐oxidant and anti‐apoptosis function. We firstly confirmed the cardioprotective effects of CGA in transverse aortic constriction (TAC)‐induced heart failure mouse model, through mitigating the TNF‐α–induced toxicity. We further used TNF‐α‐induced cardiac injury in human induced pluripotent stem cell‐derived cardiomyocytes (hiPSC‐CMs) to elucidate the underlying mechanisms. CGA pre‐treatment could reverse TNF‐α–induced cellular injuries, including improved cell viability, increased mitochondrial membrane potential and inhibited cardiomyocytes apoptosis. We then examined the NF‐κB/p65 and major mitogen‐activated protein kinases (MAPKs) signalling pathways involved in TNF‐α–induced apoptosis of hiPSC‐CMs. Importantly, CGA can directly inhibit NF‐κB signal by suppressing the phosphorylation of NF‐κB/p65. As for the MAPKs, CGA suppressed the activity of only c‐Jun N‐terminal kinase (JNK), but enhanced extracellular signal‐regulated kinase1/2 (ERK1/2) and had no effect on p38. In summary, our study revealed that CGA has profound cardioprotective effects through inhibiting the activation of NF‐κB and JNK pathway, providing a novel therapeutic alternative for prevention and treatment of heart failure. [ABSTRACT FROM AUTHOR]

Objective: Acute triglyceride‐lowering therapy is crucial in the early treatment of hypertriglyceridemia‐induced pancreatitis. This study aimed to compare the efficacy of continuous i.v. infusion of insulin and heparin therapy (IHT) and plasma exchange to lower triglyceride levels in the acute phase of hypertriglyceridemia‐induced pancreatitis. Methods: A retrospective observational study was conducted in a tertiary teaching hospital. Patients with hypertriglyceridemia‐induced pancreatitis were consecutively enrolled from 2012 to 2017. Serum triglyceride levels and clinical data during hospitalization were collected. The primary outcome was the rapid reduction of triglyceride levels. Results: Of the 62 patients enrolled, 34 (54.8%) were treated with IHT and the others with plasma exchange. A reduced triglyceride level of (66.9 ± 21.5)% after the first plasma exchange session and that of (75.0 ± 14.6)% after the first day of IHT were observed. There were no significant differences in the reduction of triglyceride (F = 0.334), high sensitivity C‐reactive protein (F = 0.127) and the acute physiology and chronic health evaluation II score (F = 2.589) between the two groups (all P > 0.05). The medical cost during hospitalization was significantly lower in the IHT group than in the plasma exchange group (RMB [59 512.4 ± 23 645.1] vs RMB [89 461.9 ± 48 324.0], P < 0.05). Adverse effects were observed in six patients in the plasma exchange group but none in the IHT group. Conclusion: As a minimally invasive and economical strategy, IHT is effective and non‐inferior to plasma exchange in achieving a rapid reduction of triglyceride levels. [ABSTRACT FROM AUTHOR]

Abstract: This work demonstrates the use of a NiCu electrocatalyst prepared by hydrothermal method with different Ni/Cu mass ratios (70:30, 50:50 and 30:70) supported on carbon nanotubes (CNTs), which was studied with regards to its electrochemical behavior in the ammonia oxidation reaction and direct ammonia microfluidic fuel cell (DAMFC) performance. XRD and SEM‐EDX showed the formation of NiCu alloy while TEM showed the particles size to be 15–20 nm. Cyclic voltammetry and chronoamperometry showed that NiCu had higher catalytic activity than pure Ni and pure Cu, and that the active species was a NiCu oxyhydroxide. In DAMFC tests, 50 wt % Ni50Cu50/CNTs was found to be the most suitable one since it showed a 43 % higher peak power density and 65 % higher maximum current density than Ni electrode. The improved performance was attributed to the NiCu oxyhydroxides formation, which improved the anodic catalytic activity by increasing amounts of active sites and the combined electronic effect of the Ni‐Cu bimetallic catalysts. [ABSTRACT FROM AUTHOR]

Abstract: Oxygen and nitrogen co‐enriched hierarchical porous carbon hollow microspheres are synthesized by using biomass‐derivative sodium lignosulfonate as a feedstock through a facile and scalable process. This four‐step synthesis process involves spray drying, thermal stabilization, carbonization, and post nitric acid modification. The as‐obtained carbon exhibits a moderate but efficient porosity (specific surface area of 991 m2 g−1, total pore volume of 0.75 cm3 g−1), small particle size of 0.2–5 μm, high electrode density of 0.45 g cm−3, and abundant surface oxygen/nitrogen species (13.12 at.%/0.97 at.%). Its electrochemical performance is evaluated by assembling into supercapacitors in 7 M KOH electrolyte. The three‐electrode cell presents a high gravimetric capacitance of 284 F g−1 at 0.1 A g−1 and good rate capability of 43.6 % at 20 A g−1. While the two‐electrode cell gives an impressive volumetric capacitance of 21.2 F cm−3 at 0.1 A g−1, marvelous volumetric energy density of 2.9 Wh L−1 at 11.3 W L−1, and remarkable cycling stability of 93.4 % capacitance retention after 10000 cycles, which is superior or comparable to that of commercial activated carbon. [ABSTRACT FROM AUTHOR]

Liddle syndrome, an autosomal dominant form of monogenic hypertension, has been regarded as a rare disorder, which leads to many Liddle syndrome patients being misdiagnosed and experiencing severe complications at an early age. Little is known about the prevalence of Liddle syndrome. In this study, the authors investigated the prevalence of Liddle syndrome confirmed by genetic testing among young hypertension patients of undetermined causes in China. A total of 330 hypertensive patients aged 14 to 40 years after exclusion of common secondary causes of hypertension were enrolled and serum potassium concentrations were measured. Patients with hypokalemia underwent genetic testing of the 13th exon of genes encoding β and γ subunits of the epithelial sodium channel (ENaC). Diagnosis was established by identification of mutations that destroy the PY motif of ENaC. Five patients were diagnosed with Liddle syndrome (prevalence, 1.52%), as well as 12 of their relatives. These patients with Liddle syndrome presented with an earlier onset of hypertension, a stronger family history of hypertension, and higher blood pressure than those with essential hypertension. All patients had hypokalemia and suppressed plasma renin activity. The results demonstrated that Liddle syndrome is an important etiology of hypertension in this young population. Screening of Liddle syndrome should focus on young hypertension patients, particularly those with early penetrance, hypokalemia, and low renin levels after exclusion of common secondary causes. [ABSTRACT FROM AUTHOR]

A facile and green electrochemical method for the fabrication of three-dimensional porous nitrogen-doped graphene (3DNG) modified electrode was reported. This method embraces two consecutive steps: First, 3D graphene/polypyrrole (ERGO/PPy) composite was prepared by electrochemical co-deposition of graphene and polypyrrole on a gold foil. Subsequently, the ERGO/PPy composite modified gold electrode was annealed at high temperature. Thus 3DNG modified electrode was obtained. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy were used to characterize the structure and morphology of the electrode. The electrode exhibits excellent electroanalytical performance for the reduction of hydrogen peroxide (H2O2). By linear sweep voltammetric measurement, the cathodic peak current was linearly proportional to H2O2 concentration in the range from 0.6 μM to 2.1 mM with a sensitivity of 1.0 μA μM−1 cm−2. The detection limit was ascertained to be 0.3 μM. The anti-interference ability, reproducibility and stability of the electrode were carried out and the electrode was applied to the detection of H2O2 in serum sample with recoveries from 98.4 % to 103.2 %. [ABSTRACT FROM AUTHOR]

This paper reports the fabrication of Au nanoparticles (Au NPs)-Ni-Al layerd double hydroxide (LDH) composite film by one step electrochemical deposition on the surface of a glass carbon electrode from the mixture solution containing HAuCl4 and nitrate salts of Ni2+ and Al3+. Improved conductivity was obtained by Au NPs codeposited on LDH film. The synergic effect of LDHs and Au NPs dramatically improves the performance of L-cysteine electro-oxidation, displaying low oxidation peak potential (0.16 V) and high current response. Thus the electrode was used to sense L-cysteine, showing good sensitivity and selectivity. [ABSTRACT FROM AUTHOR]

The article focuses on a warfarin metabolomics study related to the procoagulant ethanolamide plasma lipids as of May 2014. Topics discussed include the use of tandem mass spectroscopy (MS/MS) for identifying metabolic features as palmitoylethanolamide (PEA) and stearoylethanolamide (SEA), the correlation between change of PEA by warfarin with the change of SEA and complications of oral anticoagulant therapy.

BACKGROUND Xylanases have attracted much attention because of their potential applications. Unfortunately, the commercialization of xylanases is limited by their low catalytic activities. The aim of this study was to improve the activity of a xylanase by optimization of the expression conditions and to investigate its characterization. RESULTS The activity of recombinant AuXyn11A ( reAuXyn11A), a family 11 xylanase from Aspergillus usamii E001 expressed in Pichia pastoris GS115, reached 912.6 U mL−1 under the optimized conditions, which was 2.14 times as high as that expressed using the standard protocol. After the endogenous 18-aa propeptide had been processed in P. pastoris, reAuXyn11A (188-aa mature peptide) was secreted and purified with a specific activity of 22 714 U mg−1. It displayed maximum activity at pH 5 and 50 °C and was stable in the pH range 4-8 and at a temperature of 45 °C or below. Its activity was not significantly affected by most metal ions and EDTA. Xylooligosaccharides ranging from xylobiose ( X2) to xylohexaose ( X6) were produced from insoluble corncob xylan by reAuXyn11A. CONCLUSION Its high specific activity and good enzymatic properties suggest that reAuXyn11A is a potential candidate for applications in industrial processes. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A mesophilic xylanase from Aspergillus oryzae CICC40186 (abbreviated to AoXyn11A) belongs to glycoside hydrolase family 11. The thermostability of AoXyn11A was significantly improved by substituting its N-terminus with the corresponding region of a hyperthermostable family 11 xylanase, EvXyn11TS. The suitable N-terminus of AoXyn11A to be replaced was selected by the comparison of B-factors between AoXyn11A and EvXyn11TS, which were generated and calculated after a 15 ns molecular dynamic (MD) simulation process. Then, the predicted hybrid xylanase (designated AEx11A) was modeled, and subjected to a 2 ns MD simulation process for calculating its total energy value. The N-terminus substitution was confirmed by comparing the total energy value of AEx11A with that of AoXyn11A. Based on the in silico design, the AEx11A was constructed and expressed in Pichia pastoris GS115. After 72 h of methanol induction, the recombinant AEx11A (reAEx11A) activity reached 82.2 U/mL. The apparent temperature optimum of reAEx11A was 80°C, much higher than that of reAoXyn11A. Its half-life was 197-fold longer than that of reAoXyn11A at 70°C. Compared with reAoXyn11A, the reAEx11A displayed a slight alteration in Km but a decrease in Vmax. Biotechnol. Bioeng. 2013; 110: 1028-1038. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

SUMMARY Aims: It is unknown whether hypothermia can disrupt the progress of epileptogenesis. The present study aimed to determine the effect of hypothermia on brain edema and epileptogenesis and to establish whether brain edema is associated with epileptogenesis after severe status epilepticus (SE). Methodology: Rats were injected with a single dose of Kainic acid (KA) to produce either chronic epileptic rats (rats with spontaneous recurrent seizure, SRS) or rats without spontaneous recurrent seizure (no-SRS rats). A second KA injection was used to induce SE in SRS rats and in no-SRS rats. The number of SRS was counted and the brain edema induced by SE was assessed by brain water content measurement. The cognitive function was assessed by the radial-arm maze (RAM) test. Results: A second KA injection resulted in brain edema that was more severe in SRS rats than in no-SRS rats. After second injection of KA, hypothermia treatment attenuated the KA induced brain edema and reduced the SRS attack in SRS rats. Additionally cognitive function was better in hypothermia-treated SRS rats than in nomothermia treated SRS rats 1 month after the second KA injection. Conclusions: Hypothermia treatment immediately after SE not only exhibited protective effects against the chronic spontaneous recurrent convulsant seizures but also improved cognitive function. These antiepileptogenic properties of hypothermia may be related to its attenuating effect on brain edema induced by SE. They therefore suggest that brain edema may be involved in the progress of epileptogenesis. [ABSTRACT FROM AUTHOR]

Mutations of the receptor tyrosine kinase KIT are linked to certain cancers such as gastrointestinal stromal tumors (GISTs). Biophysical, biochemical, and structural studies have provided insight into the molecular basis of resistance to the KIT inhibitors, imatinib and sunitinib. Here, solution-phase hydrogen/deuterium exchange (HDX) and direct binding mass spectrometry experiments provide a link between static structure models and the dynamic equilibrium of the multiple states of KIT, supporting that sunitinib targets the autoinhibited conformation of WT-KIT. The D816H mutation shifts the KIT conformational equilibrium toward the activated state. The V560D mutant exhibits two low energy conformations: one is more flexible and resembles the D816H mutant shifted toward the activated conformation, and the other is less flexible and resembles the wild-type KIT in the autoinhibited conformation. This result correlates with the V560D mutant exhibiting a sensitivity to sunitinib that is less than for WT KIT but greater than for KIT D816H. These findings support the elucidation of the resistance mechanism for the KIT mutants. [ABSTRACT FROM AUTHOR]

Shiga toxin-producing Escherichia coli (STEC) is associated with hemolytic uremic syndrome (HUS). Although most clinical isolates of STEC produce hemolysin (called enterohemolysin), the precise role of enterohemolysin in the pathogenesis of STEC infections is unknown. Here we demonstrated that E. coli carrying the cloned enterohemolysin operon (hlyC, A, B, D genes) from an STEC human strain induced the production of interleukin-1β (IL-1β) through its mRNA expression but not tumor necrosis factor-α from human monocytes. No IL-1β release was observed with an enterohemolysin (HlyA)-negative, isogenic E. coli strain carrying a mutation in the hlyA gene. The data suggest that enterohemolysin, a pore-forming toxin, induces the production of IL-1β, which is one of serum risk markers for HUS. [Copyright &y& Elsevier]

ABSTRACT Background. Clarithromycin-resistant Helicobacter pylori (CRHP) has increasingly been isolated from patients in Japan. The aim of our study was to test whether proton pump inhibitors (PPIs) and their thioether derivatives, which are secreted into the gastric mucosa, could inhibit the growth and motility (a factor in colonization) of CRHP. Materials and Methods. CRHP was isolated from patients who had experienced gastritis or peptic ulcers in Tokyo and Niigata. Drugs and related agents tested were omeprazole, lansoprazole, rabeprazole, the thioether derivative of rabeprazole (rabeprazole-TH), clarithromycin, amoxicillin and metronidazole. The MICs of the drugs and agents for H. pylori strains were determined by the agar dilution method. Bacterial swimming in a liquid layer was examined under an inverted, phase-contrast microscope. Results. The PPIs and rabeprazole-TH, but not the anti-H. pylori agents, inhibited the motility of CRHP at both pH 7.4 and 6.0. The concentrations (µg/ml) necessary to inhibit 50% of the motility at pH 7.4 were 0.25–0.5, 8–32, 8–16 and 128–256 for rabeprazole-TH, rabeprazole, lansoprazole and omeprazole, respectively. Rabeprazole-TH exibited the strongest inhibitory effect against the growth of CRPH (MIC, 0.5 µg/ml). Conclusion. Rabeprazole-TH, which is secreted into the gastric mucosa, had the strongest inhibitory action against both the growth and motility of CRHP, suggesting that it is a potential novel agent for CRHP eradication. [ABSTRACT FROM AUTHOR]

5 examples [ABSTRACT FROM AUTHOR]

The title compound [systematic name: (7a S*,13a R*,13b R*,13c S*)-10-oxo-dodeca­hydro-1 H,5 H,8 H-dipyrido[2,1- f:3′,2′,1′- ij][1,6]naphthyridinium 3-methyl-4-nitro-1-(4-nitro­phen­yl)-5-oxo-2-pyrazolinate 0.28-hydrate], C15H25N2O+·C10H7N4O5−·0.28H2O, consists of one matrinium cation [matrine is (7a S,13a R,13b R,13c S)-dodeca­hydro-1 H,5 H,8 H-dipyrido[2,1- f:3′,2′,1′- ij][1,6]naphthyridin-10-one], one picrolonate anion and 0.28 water mol­ecules, held together by N—H⋯O and O—H⋯O hydrogen bonds. Disordered C atoms in the ring bearing the carbonyl group of the matrinium cation cause the ring to appear in half-chair and half-boat conformations. [ABSTRACT FROM AUTHOR]

The title compound, (C(6)H(14)N(2))[Cr(2)O(7)], consists of a diazabicyclo[2.2.2]octane-1,4-diium cation and a discrete dichromate anion, which are linked in the crystal by N-H...O hydrogen bonds. The cation is ordered and distorted, owing to the confinement and twist of the hydrogen bonds involved. Two CrO(4) tetrahedra are joined through a shared O atom to form the dichromate anion. Chiral supramolecular chains of the title compound are built up via N-H...O hydrogen bonds, and C-H...O interactions play subordinate roles in forming the structure.